Apparatus for dispensing catalyst coated fibers and cementitious material onto a surface

ABSTRACT

GLASS FIBER STRANDS COATED WITH A CEMENTITIOUS MATERIAL ARE FORCEFULLY PROJECTING FROM A SOURCE BY CENTRALLY ENTRAINING CONTINUOUS FIBER STRANDS ENSHROUDED BY A LIQUID CATALYST IN THE CEMENTITIOUS MATERIAL FOR DEPOSIT ONTO A RECEIVING SURFACE AS THE CATALYST MIXES WITH THE CEMENTITIOUS MATERIAL.

United States Patent M US. Cl. 156-166 4 Claims ABSTRACT OF THEDISCLOSURE Glass fiber strands coated with a cementitious material areforcefully projecting from a source by centrally entraining continuousfiber strands enshrouded by a liquid catalyst in the cementitiousmaterial for deposit onto a receiving surface as the catalyst mixes withthe cementitious material.

This invention relates to dispensing and use of cementitious materialsuch as a resin and a fibrous material and, more particularly, todisposition of and transport by continuous fiber rovings of an auxiliarycooperating agent such as a liquid catalyst which is mixed with materialsuch as a resin or the like as it is dispensed.

The present invention relates to improvements in the invention disclosedin US. Pat. No. 3,232,557, and application Ser. No. 722,678 nowabandoned, filed Mar. 20, 1958. It is to be understood that the presentinvention is not limited to the environment of the specific disclosurein Pat. 3,232,557, and that it may be used generally to facilitatedispensing of fibrous material under pressure with dispensers for fluidcementitious material.

It is an object of the present invention to provide for coating andtransporting of a catalyst coating by a continuous fiber roving such asfiber glass bundled together in continuous untwisted strands and to mixthe cementitious material with the catalyst while contacting the fiberswith resin.

The use of commercially available fiber rovings ordinarily packaged inspools has been found to introduce undesirable effects. It has beenfound to be diflicult to maintain a dispensing system in operation forextended periods by reason of the accumulation of unwanted debris whichtends to foul the dispensing system. In addition, the movement of highlyinsulating fiber strands generates electrostatic charges which produceundesirable force fields.

Fibers suitably treated can be dispensed, avoiding the diflicultiesabove mentioned. In Patent 3,232,557, continuous fibers are to bedispensed from a spool of rovings of continuous filaments.

In accordance with the present invention there is provided a liquidcatalyst disposed as to enshroud the roving as it travels through thegun.

For a more complete understanding of the present invention and forfurther objects and advantages thereof, reference may now be had to thefollowing description taken in conjunction with the accompanyingdrawings in which:

FIG. 1 illustrates a suitable system for dispensing a mixture ofcementitious material with fibers enshrouded with an atomized liquidcatalyst;

FIG; 2 is a top view of the gun of FIG. 1; and

FIGS. 3 and 4 illustrate modified forms of nozzle caps.

Referring now to FIG. 1, a dispensing gun is comprised of a nozzle 11which is preferably in the form of a pair of coaxial elements, a nozzle11a and a cap 11b. Nozzle 11b is flow connected to a pipe 12. Pipe 12 iscoupled to a valve 13, the input of which leads by way of a line 14 to afiber dispensing pot or container 15. A

3,674,600 Patented July 4, 1972 compressed air line 16 is connected topot 15 in accordance with prior Pats. Nos. 3,232,557 or 3,305,150. Line16 is also connected to a resin tank 17 and to an atomizer 18 leadingfrom a liquid catalyst tank 19. Line 29 from atomizer 18 is connected byway of valve 21 and tube 22 to a lateral port 19 in one side of line 12.

The container 15 is provided for receiving a spool 40 of fiber rovingssuch as fiber glass rovings wherein the fibers are bundled and extendwithout being twisted throughout the entire spool. The container 15comprises a chamber which can be pressurized. In the form shown itconsists of a deep open topped receptacle onto which a lid may besecured in airtight relation. The compressor is connected to the chamber15 by way of a line 28 whereby the interior of the container 15 may bemaintained under pressure. An outlet port 41 is connected by way of thetubing 14 for delivery of the fiber rovings from the container 15 to thevalve 13 in gun 10.

The details of construction of the container shown in FIG. 1 are foundin Pat. 3,232,557, and thus will not be described further here.Alternatively, the container 15 may be of the form shown in Pat.3,305,150. In either case, the spool 40 of glass fiber rovings is placedin the container. The fibers are then delivered through line 14, valve13 and nozzle 11b to a mixing chamber in cap 11.

Resin from tank 17 is connected by line 30 to a valve 31 on the gun 10.Valve 31 is connected by tube 32 to a lateral port 33 in nozzle 11b. Bythis means the resin is delivered at a rate controlled by valve 31 tothe mixing chamber. The resin flows around the central nozzle member asto centrally entrain fibers delivered to mixing chamber 11d throughmember 11c. Member 110 may be a rigid spout or it may be resilient sothat it may fiap in chamber 11d upon flow therethrough.

Line 20 is employed in accordance with the present invention to injectinto line 12 an atomized catlayst from tank 19 to cover or wet thefibers so that the catalyst will be distributed throughout the resin inchamber 11d and thereby accelerate curing of the resin with fiberstherein as projected from nozzle cap 11a onto a form to be covered orcoated with fiber reinforced resin.

One coating material that may be employed is a resin of the aminepromoted type.

In use of such resin in accordance with the invention, liquid benzoylperoxide catalyst is used Catalyst in amounts from 20% to 30% by volumeof fiber has been found to be satisfactory. When this quantity isemployed the benzoyl peroxide is ultimately delivered to and mixed witha polyester resin by reason of spraying the same along with the glassfibers such that there is from between 0.5 to 2.0 percent of benzoylperoxide in the polyester, the ratio being by volume of benzoyl peroxidecompared to the volume of the polyester. A representative resin that hasbeen used is the resin made by Reichhold Chemical No. 32-175 under thetrade name Polylite which is promoted by, or with dimethylane analine.Enough of benzoyl peroxide clings to the fiber to set this resin.

'It will be readily appreciated that the relative proportion of catalystto polyester may be controlled by an operator in proportioning theamount of liquid benzoyl peroxide employed relative to the amount offiber and resin employed in the given operation.

The system provides for the deposit of a glass reinforced resin bodywhich Will set at room temperatures and, thus, is of enhanced value inconnection with operations where resins are to be sprayed. Further, ithas the distinct advantage in that all materials are mixed in cap 11a.

The catalyst-coated fibers, the resin and the compressed air aredelivered to the nozzle 11 in controlled amounts.

Thus, there is provided a mixing chamber 11d within the nozzle whereinthe fibers and the resin are thoroughly mixed before being ejectedthrough the orifice 11e. Controlled amounts of air with catalytic agentcan be introduced into the mixture to control the nature of the mixtureto be ejected from the orifice 11e. It will be recognized that the guncan be used to dispense resin alone, fibers alone, compressed air alone,or any combination of the three. Thus, the nozzle 11 provides forprewetting the fibers with a resin which is responsive to the catalystenshrouding the fibers so that when dispensed from the nozzle 11 theresin may be caused to set. The setting rate may be controlled by theamount of catalyst employed.

By atomizing the liquid catalyst in the air line the catalyst saturatesthe fiber before the fiber reaches the resin.

The atomizer is conventional, known in the art as a Nugent dripper, andmay be located for convenience at the fiber pot or at compressor 26. Theatomizer preferably is adjustable to meter the catalyst.

By this means, catalytic agents can be applied to a number ofself-hardening, pumpable materials, such as methyl ethyl ketoneperoxides, benzoyl peroxides, and the water impregnated polyesters.Also, foaming agents can be applied to a number of materials that cannotbe premixed and pumped because a pump destroys the foam. Moreparticularly, a gun such as shown in FIG. 1, but of larger capacity maybe used to spray fiber reinforced portland cement. In such case,atomized caustic soda wetting the fibers will cause the cement to foamand thus permits formation of fiber reinforced concrete structureshaving characteristics attributable to foam therein but not possibleunder conventional practices. Magnesium chloride may be used with suchcement, in the manner herein disclosed, to accelerate setting of thecement, a uniform mix of agent and cement being produced.

In this system, there is required only one source container or pot,reducing the clean-up problem. The pot life of the resins used isextended. Clean-up of the gun requires only removing the cap 11a anddipping the nozzle 11b and cap 11a in a solvent.

The foregoing discussion of resin systems has dealt particularly withthe methyl ethyl ketone peroxide catalytic agent. There are severalother catalyst agents that may be employed to produce the same endresults. For example, some would be chosen to inhibit ultra violetlight, some for fire protection, etc.

FIGS. 3 and 4 show variations in the cap 11a. Cap 50 would be employedwhen foaming agents are to be employed or where more mixing is required.Cap 51 would be chosen to control the mix or projection. Either may beused with a fixed or flopping action in spout 110, FIG. 1.

Having described the invention in connection with certain specificembodiments thereof, it is to be understood that further modificationsmay now suggest themselves to those skilled in the art and it isintended to cover such modifications as fall within the scope of theappended claims.

What is claimed is:

1. In a system where continuous fibers are to be dispensed from a spoolor rovings of continuous fibers in a container for receiving said spooltherein with a fiber line extending to a nozzle, the combination of (a)means to propel fiber entrained in air flow through said fiber line tosaid nozzle;

(b) means for introducing atomized liquid catalyst into said flow at apoint adjacent said nozzle to enshroud the roving as it travels to saidnozzle;

(c) structure forming a mixing chamber in said nozzle through which saidfibers pass; and

(d) means for delivering a cementitious material to said chamber to coatsaid fibers and mix said catalyst with said material as the fibers andmaterial are dispensed.

2. The combination set forth in claim 1 in which said catalyst is liquidbenzoyl peroxide and said spool is fiber glass rovings.

3. The combination set forth in claim 1 in which said catalyst is methylethyl ketone peroxide and said spool is fiber glass rovings.

4. The combination set forth in claim 1 wherein the proportion of saidliquid catalytic agent is adjustable in relation to the quantity offiber being deposited into the mixture.

References Cited UNITED STATES PATENTS 3,296,051 1/1967 Harpfer et all56285 3,329,543 7/1967 Arthur et a1. 156l66 3,480,498 11/1969 Paul156285 3,393,109 7/1968 Dorst 156-279 BENJAMIN R. PADGETT, PrimaryExaminer S. J. LECHERT, JR., Assistant Examiner U.S. Cl. X.R.

